Self-contained heat exchangers comprising a fluid reservoir, fan, motor, and radiator are well known. See, for example, U.S. Pat. Nos. Erbe et al. 3,196,939 issued Jul. 27, 1965 and Opitz 2,025,216, issued Dec. 24, 1935. In addition, O'Brien 1,189,470 discloses a generally cylindrically shaped air cooler and dehumidifier including a single length of pipe for carrying a heat exchange fluid, the pipe being arranged to form a plurality of spaced apart, concentric coils. The coils are arranged with a common horizontal axis, forming a plurality of air passages coaxially aligned with a central air passage.
Presently known self-contained heat exchange systems are unsatisfactory in several regards. For example, systems wherein the fluid pump is external to the airflow path do not maximize heat convection from the pump. Moreover, to the extent the heat exchange surface of the fluid reservoir is isolated from the airflow path, heat exchange efficiency may be impaired.
In addition, many existing systems are constructed with fluid circulation tubing and fittings on the outside surface of the heat exchanger, rendering these components susceptible to damage from inadvertent contact with external sources.